Glossary of Medical Terms – R

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Effects of ionizing and nonionizing radiation upon living organisms, organs and tissues, and their constituents, and upon physiologic processes. It includes the effect of irradiation on drugs and chemicals

Radiation Therapy

Treatment to kill cancer cells with high energy rays from x-rays or other sources

Radiography

X-ray

Radiological

X-ray related

Ranitidine

Drug used to control ulcer pain and to aid in the healing of peptic ulcers by cutting down on the amount of acid the stomach secretes

Rate

The number of events happening divided by the length of time over which they happen. A rate of change is the amount of change happening in a interval divided by the length of the interval

Rate of infection

Degree of speed or progression of an epidemic

RBC

Red Blood Cell, Red Blood Count

RBC (Red Blood Cell) Count

The RBC count is most useful as raw data for calculation of the erythrocyte indices MCV and MCH. Decreased RBC is usually seen in anemia of any cause with the possible exception of thalassemia minor, where a mild or borderline anemia is seen with a high or borderline-high RBC. Increased RBC is seen in erythrocytotic states, whether absolute (polycythemia vera, erythrocytosis of chronic hypoxia) or relative (dehydration, stress polycthemia), and in thalassemia minor [see “Hemoglobin,” below, for discussion of anemias and erythrocytoses]. Hemoglobin, Hematocrit, MCV (Mean Corpuscular Volume), MCH (Mean Corpuscular Hemoglobin), MCHC (Mean Corpuscular Hemoglobin Concentration). Strictly speaking, anemia is defined as a decrease in total body red cell mass. For practical purposes, however, anemia is typically defined as hemoglobin

RBV

Ribavirin

RCT

Rrandomized Controlled Ttrial

RDA

Recommended Daily Allowance

RDW – Red cell Distribution Width

Red cell distribution width is a numerical expression which correlates with the degree of anisocytosis (variation in volume of the population of red cells). Some investigators feel that it is useful in differentiating thalassemia from iron deficiency anemia, but its use in this regard is far from universal acceptance. The RDW may also be useful in monitoring the results of hematinic therapy for iron-deficiency or megaloblastic anemias. As the patient’s new, normally-sized cells are produced, the RDW initially increases, but then decreases as the normal cell population gains the majority

RE

Regional Eneritis

Reactive Oxygen Species

(ROS) Molecules including free radicals and other oxygen species

Reabsorption

Absorbing again

Reagent

Reactive substance

Rebefacient

Substance used externally that causes redness of the skin

Rebound Acid Secretion

Return of acid secretion when the effect of antacid is gone. Rebound effect may be more severe than before treatment

Rebound Congestion

Return of congestion when the effect of medication is gone. Rebound effect may be more severe than before treatment

Receptor

A specific molecule on the surface of a cell which is used by a virus for attachment

Receptor Site

Structure of protein on the outside of the cell membrane – receptor sites allow cells to identify each other and serve as attachment points for biological substances that produce a alterations in cell function. Viruses use receptor sites to identify a host cell and attach to it

Recombinant

Produced from more than one source. Relating to or exhibiting genetic recombination, Relating to or containing recombinant DNA. Produced by recombinant DNA technology. An individual exhibiting recombination

Recombinant DNA

DNA chain that has been altered through insertion of a new sequence using bioengineering. Genetically engineered DNA prepared in vitro by cutting up DNA molecules and splicing together specific DNA fragments usu. from more than one species of organism

Reconstitution

Regeneration, continuous repair of progressive destruction of tissues.
Returning a substance to its original form or state

Two abdominal muscles that run from the lower ribs to the pelvis on either side of the midline and are responsible for maintaining abdominal tone

Recurrent

Recurring, returning, turning back in its course

Red Blood Cell

Any of the hemoglobin-containing cells that carry oxygen to the tissues and are responsible for the red color of blood

Red Clover

Used as a antibiotic, appetite suppressant, blood purifier, and relaxant

Red Raspberry

Rich in iron and nutrients, used to treat anemia

Red Root

Ceanothus Americanus–Exhibits astringent, antispasmodic, antisyphilitic expectorant and sedative properties. Used to treat asthma, chronic bronchitis, consumption, dysentery, and whooping cough, also as a mouth wash and gargle, and as an injection in gleet, gonorrhea, and leucorrhoea

Reducers

Compounds such as antioxidants that accept electrons

Reducing Agent

(Reductant) The electron donor in an oxidation-reduction reaction

REE

Resting Energy Expenditure

Reference

Of known potency and used as a standard in the biological assay of a sample of the same drug of unknown strength

Reflux

Return flow, when liquid backs up into the esophagus from the stomach. Backward flow

Reflux Esophagitis

Inflammation of the esophagus because of the backwash of stomach contents into the esophagus

Refractory

Not responding to treatment

Refrigerant

Substance capable of cooling body temperature or allaying thirst

Regurgitation

Backward flow of gastric juice, gas, or small amounts of food from the stomach to the mouth

Rehmannia Root

A demulcent, laxative, provides energy, stops bleeding, and strengthens the immune system. Used to treat anemia, fatigue, and to promote the healing of broken bones

Reishi Mushroom

Also called Ling-Zhi. Used as a sedative and tonic. Used to lower cholesterol, prevent blood clots, help prevent the growth of tumors, Arthritis, Chronic Fatigue Syndrome, Diabetes, Hypertension, Nervous exhaustion and Liver disorders

Rejection

an immune response against grafted tissue, which, if not successfully treated, results in failure of the graft to survive

Relapse

Return of the symptoms of disease after the disease was thought to be cured

Relative Risk

The proportion of diseased people amongst those exposed to the relevant risk factor divided by the proportion of diseased people amongst those not exposed to the risk factor. This should be used in those cohort studies where those with and without disease are followed to observe which individuals become diseased.

Remission

Partial or complete disappearance of the symptoms of a disease. This may be naturally occurring or as the result of therapy

Renal

Kidney related

Renin

Enzyme

Release

The stage of viral replication at which virus particles escape the infected cell

Replicated

Folded over or backward; folded back upon itself; as, a replicate leaf or petal; a replicate margin of a shell

Replication

Duplication. A turning back of a part so as to form a duplication. The process of duplicating or reproducing, as the replication of an exact copy of a polynucleotide strand of DNA or RNA. Replicatio means a fold backwards

Reproductive Ratio–Basic reproductive ratio

Ro, a dimensionless parameter which encapsulates the biological details of different transmission mechanisms. For microparasites, Ro, is defined as the average number of secondary cases of infection to which one primary case gives rise throughout its infectious period if introduced into a defined population consisting solely of susceptible individuals. Effective reproductive ratio – R, The number of secondary cases (microparasites) or female offspring (macroparasites) produced in a host population not consisting entirely of susceptible individuals (microparasites) or within which density dependent constraints limit parasite population growth (macroparasites)

Research

Careful, a diligent search, a close searching, studious inquiry or examination

Resection

Removal of any part of the body. Whatever is removed is said to have been resected

Resistance

The reduction, due to genetic selection, of susceptibility of a parasite or its vector to chemotherapy. The ability of a host to resist a pathogen

Respirations

Breaths; the act of inhaling and exhaling

Response Rate

Percentage of treated patients who respond positively to medical treatment

Restorative

Substance that helps to bring a person to consciousness or back to normal vigor, Out of alpha series

Retard

Delay

Retardation

Delaying

Retinopathy

Eye disorder that does not cause inflammation but results from changes in the eye (retinal) blood vessels

Retraction

Moving backwards. Drawing back, the condition of being drawn back

Retransplantation

Due to organ rejection or transplant failure, some patients need another transplant and return to the waiting list.

Re-treatment

Starting treatment again after the patient has had a relapse of a disease or did not respond to the first treatment

Retrobulbar

Behind a link

Retrograde

Backwards

Retrospective Study

A study in which people are enrolled and then have their history of risks, infections or disease measured

Retrovaccination

The inoculation of a cow with human vaccine virus

Retroviridae

Viruses with a single stranded RNA genome (Class VI). On infecting a cell the virus generates a DNA replica by action of its virally coded reverse transcriptase. Oncovirinae are one of three subclasses of retroviruses, the others being Lentivirinae and Spumavirinae

Retroviral Vector

See Retroviridae. Retroviral vectors are used in the genetic modification of cells as a means of introducing foreign DNA into the genome. For example: retroviral vector ‘s encoding histochemical markers (reporter genes) are used in the study of neural cell lineage in vertebrates. Retroviral vector’s may contain the bacterial lacZ gene that encodes for the enzyme _ galactosidase. When the retrovirally infected cells divide, they replicate the foreign DNA. Progeny of infected cells will therefore express the protein and can then be detected histochemically

Retrovirus

Any of a family of RNA viruses containing reverse transcriptase in the virion. Retroviruses proliferate by a process that is the reverse of normal viruses. Reverse transcriptase enables the virus to convert viral RNA into DNA. This reverses the normal process of transcription where DNA is converted into RNA

Reverse Transcriptase

RNA directed DNA polymerase. Enzyme first discovered in retroviruses, that can construct double stranded DNA molecules from the single stranded RNA templates of their genomes. Reverse transcription now appears also to be involved in movement of certain mobile genetic elements, such as the Ty plasmid in yeast, in the replication of other viruses such as Hepatitis B and possibly in the generation of mammalian pseudogenes

Reye’s Syndrome

An acute disease in children characterized by vomiting, hepatic injury with fatty vacuolization, central nervous system damage, and hypoglycemia

Considered a mild laxative that produces a soft stool 6-10 hours after ingestion. Works well in children because of its mild action

RI

Regional Ileitis

RIBA

Recombinant Immunoblot Assay–Assay that verifies the presence of Hepatitis C antibodies in the bloodstream

Ribavirin

Drug initially used in the treatment of asthma. Now being used in the treatment of Hepatitis C in conjuction with Interferon. An antiviral medicine

Riboflavin

Vitamin B-2. A B-complex vitamin that acts as a coenzyme that activates the breakdown and utilization of carbohydrates, fats and proteins. Essential for cellular oxidation and necessary for healthy skin and eyes. Helps in the formation of antibodies & red blood cells; is necessary for the maintenance of good vision, nails & hair; alleviates eye fatigue, promotes general health. A deficiency of Riboflavin may result in bloodshot eyes, cracks & sores in the mouth & lips, dermatitis, digestive disturbances, itching & burning eyes, purplish tongue, retarded growth, trembling, sluggishness, and oily skin

Ribosome

One of the minute granules free in the cytoplasm or attached to the endoplasmic reticulum of a cell, containing a high concentration of RNA. The cell’s factories.- They are the place where all protein synthesis occurs. Messenger RNA (mRNA) messages from the nucleus are translated by the ribosomes, which build the encoded proteins. the spherical structure in a cell that assembles proteins after being fed the genetic instructions by mRNA

Rift Valley Fever

Febrile disease resembling dengue. It is caused by a mosquito-borne arbovirus

Right Lymphatic Duct

A short vessel that receives lymph from the right side of the head, neck, and thorax, the right arm, right lung, right side of the heart, and convex surface of the liver and that discharges it into the right subclavian vein at its junction with the right internal jugular vein

Rigidity

Stiffness

Rigors

Muscle rigidity or stiffness

Ringer’s Solution

An intravenous solution consisting of salt, potassium, and calcium boiled in water used to treat dehydration

Risk Factor

A habit, trait, or condition in a person that is associated with an increased chance (or risk) for developing a disease. Smoking, I.V. drug use, tattoos, needle sticks etc are considered “Risk Factors”

Risk Reduction

Behaviors or ways used to lessen the chance of getting a disease

RLQ

Right Lower Quadrant

RNA

See RNA—Ribonucleic Acid

RNA Editing

Specific alterations of RNAs, for example C_V changes that are not coded for in the genes

RNA Life

A hypothetical life form lacking DNA and protein which may have existed on early earth and in which RNA served both a genetic coding and a catalytic function

RNA Plasmid

dsRNA found in yeasts, also called killer factors. Their nomenclature is uncertain and some scientists consider them viruses

RNA Polymerase

An enzyme that polymerise ribonucleotides in accordance with the information present in DNA

RNA Primase

An RNA polymerase that synthesises a short RNA primer sequence to initiate DNA replication

RNA Primer

The primer sequence synthesised by RNA Primase

RNA Processing

Modifications of primary RNA trancripts including splicing, cleavage, base modification, capping and the addition of poly A tails

RNA — Ribonucleic Acid

Genetic material similar to DNA. It often acts as a ‘message’ that is delivered to cells, prompting them to change and prepare for reproduction. Molecules found in all cells which translate DNA genetic information into protein. RNA is much less stable than DNA, and mutates frequently during its reproduction. For this reason, all life forms (with the exception some viruses) use it only as a temporary messenger molecule to carry information that is permanently stored in DNA. A nucleic acid found in all living cells. Plays a role in transferring information from DNA to the protein-forming system of the cell

RNA Splicing

The removal of introns from primary RNA transcripts

RNA Splicing Pattern

The combination of DNA sequences copied from a gene by messenger RNA. The mRNAs transcribed from a single gene may splice together different parts of the sequence of the gene

RNA, Transfer, Amino Acyl

Intermediates in protein biosynthesis. The compounds are formed from amino acids, ATP and transfer RNA, a reaction catalyzed by aminoacyl tRNA synthetase. They are key compounds in the genetic translation process

RNA Tumor Virus

Oncovirinae. The family of retroviruses (Retroviridae) that can cause tumours. They are enveloped by membrane derived from the plasma membrane of the host cell, from which they are released by budding without lysing the cell. Within each virion is a pair of single stranded RNA molecules. Replication involves a DNA intermediate made on an RNA template by the enzyme reverse transcriptase

RNA Virus

Specialized set of viruses that use RNA, rather than DNA, for the storage of their genetic information. One of the reproductive substances found in the body which rejuvenates cellular activity

Rose Hips

Good for all infections and bladder problems, helps combat stress

Rosemary

Rosemary oil is a strong antioxidant, contributes substantially to the calming and soothing of tense nerves and muscles. Rosemary leaf is used as an analgesic, headache remedy, muscle stimulant and antimalarial, aids digestion and relieves cramps. Large doses of rosemary oil and other rosemary preparations can put pregnancy at risk. Avoid using rosemary oil in any amount if you are pregnant. Small doses can cause stomach, kidney and intestinal problems, and large amounts can be poisonous. If you’re pregnant, avoid using the herb altogether medicinally, although it’s okay to use as a seasoning

Round Ligament

A fibrous cord resulting from the obliteration of the umbilical vein of the fetus and passing from the navel to the notch in the anterior border of the liver and along the undersurface of that organ